Folded food carton

ABSTRACT

A folded food carton comprises a bottom panel  12 , two opposing end panels  14 , two opposing side panels  16 , four gussets  18 , and a top panel  20 . Each adjoining pair of end and side panels  14, 16  is hingedly interconnected by one of the gussets  18  each of which includes first and second gusset panels  30, 32 . In a fully folded carton configuration, the upper portion  50  of the first gusset panel  30  extends above the upper edge  52  of the second gusset panel  32  and is heat sealed to the inside surface of one of the end panels  14  such that the folded carton presents exterior panel surfaces unbroken by gussets. The top panel  20  folds over the cavity C of the folded carton and is secured in closed position by a tuck flap  42  having slot mechanisms  46  which engage with the upward-extending tabs  64  of flap mechanisms  48.

FIELD OF THE INVENTION

This invention relates to food cartons, particularly folded food cartons formed from a unitary carton blank into a recloseable portable food carton appropriate for temporary food storage.

BRIEF DESCRIPTION OF THE PRIOR ART

Folded food cartons are familiar fixtures in the “take-out” food industry. A number of folded food carton designs have been developed that can be easily and economically manufactured from treated paper. Such cartons have the significant advantage that their contents can be reheated in a microwave oven in a very short amount of time. Probably the most ubiquitous folded carton design has a deep, narrow configuration and is constructed at the manufacturing plant by folding a precut blank and fastening gussets between adjoining walls with an adhesive or by using metallic wire. Sloped walls allow them to be nested and stacked for convenient storage. They are simple to use, fairly good at preventing leaks, and are excellent for storing single food preparations that do not suffer from being compressed. Closure is commonly achieved with a pair of interlocking flaps.

A popular variant of the deep-well food carton described above is a more shallow configuration formed by fastening the gussets to the outside surface of one of the panel walls with an adhesive to connect adjoining panel walls. Configuring the gussets on the outside surfaces of the panel walls of the carton, while functional, can present a somewhat awkward or crude appearance. Although the gussets could be folded to the inside of the side and/or end panels, this requires fastening each of the overlapping folds of the gussets together and also fastening each gusset to the inside surface of the container in order to prevent the corners from pulling apart. This creates extra manufacturing steps and adds unwanted adhesive and bulkiness to the inside corners of the container. Further, although when constructing the prior art carton wherein the gussets are fastened to the outside surface of the panel walls the adhesive is applied to the outside surfaces of the container, any time adhesive is used in a food carton the specter of contaminating the food contents of the container is present to some degree.

One method for closing the container uses a single flap which is secured to the container body with a tuck flap that engages a slot on a side panel of the container. A familiar means for creating a fold line for closing the lid over the container cavity is to score the paper where the fold line is desired. While scoring the paper is effective to create fold lines, additional manufacturing operations are needed.

SUMMARY OF THE INVENTION

An improved folded food carton comprises a bottom panel extending from which are a pair of opposing end panels and a pair of opposing side panels. A plurality of foldable gussets hingedly connects the end panels with the side panels to form the bottom, end, and side panels into a carton configuration. The gussets are fastened to the inside surfaces of the end panels giving the end and side panels a smooth uninterrupted exterior surface. The gussets each comprise first and second gusset panels which are folded into an overlapping configuration when forming the panels in a carton configuration interposing the second gusset panel between the first gusset panel and the end panel. An upper portion of the first gusset panel extends above the upper edge of the second gusset panel such that it is in direct contact with the end panel. The upper portion of the first gusset panel is fastened to the end panel by heating the polymeric coating of the paper to create a strong bond. By extending the bond between the upper portion of the first gusset panel and the end panel from immediately adjacent the corner formed between the end panel and the immediately adjacent side panel, the second gusset panel is locked into place and a strong corner is formed.

Closure is achieved by use of a single fold-over top panel extending from one of the side panels. Slot mechanisms on a tuck flap on the free end of the top panel engage with notched on the opposing side panel. Hinges are formed between the top panel and the adjoining side panel, and between the tuck flap and top panel, by perforating the paper to create fold lines.

A folded food carton is thus disclosed having strong corner, smooth, unbroken exterior panel surfaces, no adhesives, and hinges not dependent on score lines.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of an unfolded carton blank for making a folded food carton according to the invention.

FIG. 2 is an upper left perspective view of the unfolded carton blank shown in FIG. 1.

FIG. 3 is an upper left perspective view of the carton blank shown in FIG. 2 showing the end, side, gusset, and top panels folded slightly inward.

FIG. 4 is an upper left perspective view of the carton blank shown in FIG. 2 showing the end, side, gusset, and top panels folded substantially inward.

FIG. 5 an upper left perspective view of the carton blank shown in FIG. 2 showing the end and side panels and gussets folded inward, the top panel folded over, and the tuck flap engaged with notches on the side panel, to form a carton configuration according to the invention.

FIG. 6 is a sectional view taken along line 6-6 of FIG. 4 showing an elevation view of a gusset in one corner of the carton.

FIG. 7 is a sectional view taken along line 7-7 of FIG. 6 showing a gusset fastened against one of the end panels.

FIG. 8 is a sectional view taken along line 8-8 of FIG. 5 showing the tuck flap engaged with one of the notches of one of the side panels.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to the drawings, a folded food carton, generally indicated at 10 in FIG. 1, comprises a bottom panel 12, two opposing end panels 14, two opposing side panels 16, including rear side panel 16R and forward side panel 16F, four gussets 18, and a top panel 20. Each end panel 14 extends from and is hingedly joined to one end of the bottom panel 12 at end panel fold lines 22. Each side panel 16 extends from and is hingedly joined to one side of the bottom panel 12 at side panel fold lines 24. Each end panel 14 is hingedly connected to an adjoining side panel 16 by one of the gussets 18. An end panel 26 extends from and is hingedly joined to the free end of each end panel 14 at end panel fold line 28. Each gusset is comprised of a first gusset panel 30 and a second gusset panel 32. The first gusset panel 30 is hingedly joined to one of the side panels 16 along a side panel corner fold line 34. The second gusset panel 32 is hingedly joined to one of the end panels 14 along an end panel corner fold line 36. The first and second gusset panels 30, 32 are hingedly interconnected along a gusset panel center fold line 38. The top panel 20 extends from and is hingedly joined to rear side panel 16R along a top panel perforation line 40. A tuck flap 42 extends from and is hingedly joined to the free end of the top panel 20 along a tuck flap perforation line 44. The tuck flap has slot mechanisms 46 for engaging with flap mechanisms 48 as discussed in greater detail below.

With reference now to FIGS. 2 and 3, the folded carton is constructed by folding the gussets 18 inwardly in the direction of the arrows A shown in FIG. 3 and folding the end and side panels 14, 16 inwardly as progressively shown in FIGS. 3 and 4. As the gussets 18 are folded inwardly, each pair of adjoining side and end panel corner fold lines 34, 36 are brought into parallel disposition to form a carton corner, and the first and second gusset panels 30, 32 are brought into an overlapping configuration as best seen in FIG. 4. When the gusset panels 30, 32 fully overlap, as shown in FIGS. 5-7 an upper portion 50 of the first gusset panel 30 extends above the upper edge 52 of the second gusset panel 32 and is brought into facing relation with the inside surface 54 of end panel 14. Preferably the upper edge 52 of the second gusset panel 32 intersects the end panel side edge 55 of the adjoining end panel 14 between the end panel fold line 22 and the end flap fold line 24, and intersects the first panel side edge 60 between the end panel fold line 28 and the first panel upper edge 58, to create a bonding area of sufficient area to securely hold a corner together and to extend laterally from the coincident side and end panel corner fold lines 34, 36.

In a preferred embodiment of the invention, the carton is manufactured with paperboard having a polymeric coating, generally a polyethylene, which, when heated, forms a secure bond with an adjoining polymer-coated surface. Thus, the upper portion 50 of the first gusset panel 30 is bonded to the inside surface 54 of the adjoining end panel 14 by heat sealing at 56. When the panels are fully folded and the gussets 18 fastened to the end panels 14, a carton is formed as shown in FIG. 5. Since the side and end panel corner fold lines 34, 36 are formed at oblique angle D with respect to side and end panel fold lines 24, 22, respectively, as shown in FIG. 1, once the carton is formed the end and side panels 14, 16 are established at oblique angle D with respect to bottom panel 12 facilitating nesting and stacking of multiple cartons.

With reference to FIG. 6 it is seen that, when the panels are fully folded and formed into a carton configuration, the upper portion 50 of the first gusset panel 30 is bounded by on top by the first panel upper edge 58, on bottom by upper edge 52 of the second panel, and on the sides by the first panel side edge 60 and the side panel side edge 62. The upper portion 50 thus extends laterally directly from the juxtaposed side and end panel fold lines 34, 36 forming a well-bonded corner.

Closure of the carton is obtained by folding top panel 20 over the cavity C formed by the bottom, end and side panels 12, 14, 16, in the direction of arrow B shown in FIG. 4. When top panel 20 is folded completely over the cavity it overlays end flaps 26. When end flaps 26 are folded over they rigidify the top edges of end panels 14 and provide a splash guard preventing spillage of contents in the carton. As mentioned above, top panel 20 is hingedly joined to rear side panel 16R at perforation line 40. Tuck flap 42 is inserted inside forward side panel 16F as indicated by arrow T in FIG. 5, with tabs 64 inserted in slots 66 as shown by arrow I. In the illustrated embodiment each slot mechanism 48 includes punch-out flap 68 defining U-shaped slot 66. It will be readily appreciated that slots can be formed in numerous shapes familiar to those in the art. Similarly, while in the illustrated embodiment tabs 64 are defined by spaced apart parallel notches 70, it will be understood that there may be numerous tab designs familiar to those having skill in the art. With reference to FIG. 8 it is seen that tabs 64 engage the undersurface 72 of the top panel 20 thereby limiting downward movement of top panel 20 into cavity C. When top panel 20 is fully folded over cavity C, with tuck flap 42 inserted on the inside of forward side panel 16F, tuck flap perforation line 44 in juxtaposition with the forward side panel top edge 74, and slot and flap mechanisms 46, 48 engaged, side walls 16 are rigidified along perforation lines 40, 44 and a strong, spill-resistant food carton, with smooth, uninterrupted exterior panel surfaces, is formed.

There have thus been described certain preferred embodiments of a folded food carton. While preferred embodiments have been described and disclosed, it will be recognized by those with skill in the art that modifications are within the true spirit and scope of the invention. The appended claims are intended to cover all such modifications. 

1. A folded food carton comprising: a bottom panel, a pair of opposing end panels extending from said bottom panel, a pair of opposing side panels extending from said bottom panel, and a plurality of foldable gussets, each said gusset hingedly connecting one of said end panels and one of said side panels, each said gusset including a first gusset panel and a second gusset panel hingedly connected with said first gusset panel, said first and second gusset panels foldable into an overlapping configuration for forming said bottom, side and end panels into a carton configuration, said first gusset panel having a an upper portion, said second gusset panel having a second panel upper edge, in said overlapping configuration said upper portion of said first gusset panel extending above second panel upper edge.
 2. The folded food carton of claim 1 wherein: said end panels have an interior surface, and said upper portion of each of said first gusset panels is fastened to said interior surface of one of said end panels.
 3. The folded food carton of claim 2 wherein: said first gusset panel and said end panel each are coated with a heat-sealable polymeric material, and said upper portion of said first gusset panel and said interior surface of said end panel are fastened together by heat sealing said polymeric material.
 4. The folded food carton of claim 3 wherein: said end panel is hingedly connected to said bottom panel at an end panel fold line, and in said overlapping configuration of said first and second gusset panels, said second panel upper edge is parallel to said end panel fold line.
 5. The folded food carton of claim 4 further comprising: each end panel having an end flap hingedly connected to said end panel at an end flap fold line, said first gusset panel having a first panel upper edge, and in said overlapping configuration of said first and second gusset panels, said first panel upper edge is parallel to said end flap fold line.
 6. The folded food carton of claim 2 wherein: said second gusset panel of each of said gussets is interposed between said first gusset panel and said end panel.
 7. The folded food carton of claim 1 wherein: said first gusset panel has a first panel upper edge, and in said overlapping configuration said upper portion of said first gusset panel extends between said first panel upper edge and said second panel upper edge.
 8. The folded food carton of claim 1 wherein: said second gusset panel of each of said gussets is hingedly connected with one of said end panels at an end panel corner fold line, said end panel has an interior surface, and said first gusset panel of said gusset is fastened to said interior surface of said end panel adjacent to said end panel corner fold line.
 9. The folded food carton of claim 8 wherein: each of said plurality of gussets is hingedly connected to one of said side panels at a side panel corner fold line, each of said plurality of gussets is hingedly connected to one of said end panels at an end panel corner fold line, said side and end panels are foldable in relation to said bottom panel into a carton configuration in which said side and end panel corner fold lines are in juxtaposition for forming a carton corner, and said upper portion of said first gusset panel is adjacent to and extends laterally from said corner.
 10. The folded food carton of claim 1 wherein: each said end panel has an end panel side edge and an end flap hingedly connected to said end panel at an end flap fold line, and each said second panel upper edge intersects said end panel side edge of one of said end panels between said end panel fold line and said end flap fold line.
 11. The folded food carton of claim 10 wherein: each of said first gusset panels has a first panel side edge, and said second panel upper edge intersects said first panel side edge between said end panel fold line and said first panel upper edge.
 12. The folded food carton of claim 1 further comprising: said side panels comprising a rear side panel, and a top panel extending from said rear side panel.
 13. The folded food carton of claim 12 further comprising: and a forward side panel having a forward side panel top edge, said top panel having a tuck flap, said top panel hingedly connected with said side panel at an top panel perforation line, said tuck flap hingedly connected with said top panel at a tuck flap perforation line, said top panel foldable along said top panel perforation line to a closed configuration, in said closed configuration said tuck flap perforation line in generally parallel juxtaposition with said forward side panel top edge.
 14. The folded food carton of claim 13 wherein: said tuck flap has at least one slot mechanism, said other of said pair of side panels has at least one flap mechanism, and in said closed configuration said slot mechanism is engaged with said flap mechanism.
 15. The folded food carton of claim 14 wherein: said slot mechanism includes perforated slot edge lines and punch-out slot-defining flaps.
 16. The folded food carton of claim 14 further comprising: an end flap extending from each of said end panels, said end flap hingedly connected with said end panel at an end flap fold line, and in said closed configuration said top panel overlays each of said end flaps.
 17. A folded food carton comprising: a bottom panel, a pair of opposing end panels extending from said bottom panel, said end panels each having an interior surface, each end panel hingedly connected to said bottom panel at an end panel fold line, a pair of opposing side panels extending from said bottom panel, and a plurality of foldable gussets, each said gusset hingedly connecting one of said end panels and one of said side panels, each said gusset including a first gusset panel and a second gusset panel hingedly connected with said first gusset panel, said first gusset panel having an upper portion, said second gusset panel having a second panel upper edge, said first and second gusset panels foldable into an overlapping configuration for forming said bottom, side, and end panels into a carton configuration, in said overlapping configuration second gusset panel disposed in overlapping engagement with said first gusset panel, said upper portion of said first gusset panel extending above said second panel upper edge, in said carton configuration said upper portion of said first gusset panel fastened to said interior surface of one of said end panels, said second gusset panel interposed between said first gusset panel and said end panel, and said second panel upper edge disposed generally parallel to said end panel fold line.
 18. The folded food carton of claim 17 wherein: each said end panel has an end panel side edge and an end flap hingedly connected to said end panel at an end flap fold line, each said second panel upper edge intersecting said end panel side edge of one of said end panels between said end panel fold line and said end flap fold line, and each of said first gusset panels has a first panel side edge and a first panel upperedge, said second panel upper edge intersecting said first panel side edge between said end panel fold line and said first panel upper edge.
 19. A folded food carton comprising: a bottom panel, a pair of opposing end panels extending from said bottom panel, said end panels each having an interior surface, each end panel hingedly connected to said bottom panel at an end panel fold line, a pair of opposing side panels extending from said bottom panel, and a plurality of foldable gussets, each said gusset including a first gusset panel and a second gusset panel hingedly connected with said first gusset panel, said first gusset panel having a first panel upper edge and an upper portion, and said first gusset panel hingedly connected to one of said side panels at a side panel corner fold line, said second gusset panel having a second panel upper edge, and said second gusset panel hingedly connected to one of said end panels at an end panel corner fold line, said first and second gusset panels foldable into an overlapping configuration for forming said bottom, side, and end panels into a carton configuration, in said overlapping configuration second gusset panel disposed in overlapping engagement with said first gusset panel, said upper portion of said first gusset panel extending between said second panel upper edge and said first panel upper edge, in said carton configuration said upper portion of said first gusset panel fastened to said interior surface of one of said end panels, said second gusset panel interposed between said first gusset panel and said end panel, said second panel upper edge disposed generally parallel to said end panel fold line, said side and end panel corner fold lines in generally parallel juxtaposition such that they form a corner, and said upper portion of said second gusset panel adjacent to and extending laterally from said corner.
 20. The folded food carton of claim 19 wherein: said first gusset panel and said end panel each are coated with a heat-sealable polymeric material, and said upper portion of said first gusset panel and said interior surface of said end panel are fastened together by heat sealing said polymeric material.
 21. A folded food carton comprising: a bottom panel, a pair of opposing end panels extending from said bottom panel, a rear side panel and a forward side panel opposing said rear side panel, said side panels extending from said bottom panel, a plurality of foldable gussets, each said gusset hingedly connecting one of said end panels and one of said side panels, each said gusset including a first gusset panel and a second gusset panel hingedly connected with said first gusset panel, said first and second gusset panels foldable into an overlapping configuration for forming said bottom, side and end panels into a carton, said first gusset panel having an upper portion, said second gusset panel having a second panel upper edge, in said overlapping configuration said upper portion of said first gusset panel extending above said second panel upper edge, and a top panel extending from said rear side panel, said top panel hingedly connected with said rear side panel at a top panel perforation line, a tuck flap extending from and hingedly connected with said top panel at a tuck flap perforation line, said tuck flap having at least one slot mechanism, said forward side panel having a forward side panel top edge and at least one flap mechanism, said top panel foldable along said top panel perforation line to a closed configuration over said side, end and bottom panels, and in said closed configuration said slot mechanism engaged with said flap mechanism and said tuck flap perforation line in juxtaposition with said forward side panel top edge.
 22. The folded food carton of claim 21 wherein: said end panels have an interior surface, said upper portion of each of said first gusset panels fastened to said interior surface of one of said end panels, and said end panel is hingedly connected to said bottom panel at an end panel fold line, in said overlapping configuration of said first and second gusset panels said second panel upper edge disposed parallel to said end panel fold line. 